Donald Trump depicted Tim Kaine’s 2006-10 tenure as governor of Virginia as a painful time of tax hike proposals and rising unemployment.

"He also oversaw a huge increase in illegal immigration, a tremendous increase," Trump told supporters at an Aug. 20 rally in Fredericksburg.

We wondered whether Trump was correct that, under Kaine’s governorship, illegal immigration spiked. We emailed the Trump campaign twice to ask about the basis of his statement, but we did not hear back.

The GOP presidential nominee’s campaign posted a version of his speech online that includes a footnote to support his claim. It’s a 2007 editorial in The Washington Times that accused Kaine of failing to crack down on unauthorized immigrants who commit crimes.

But the editorial provides no insight into whether the number of illegal immigrants in the state rose during Kaine’s tenure.

For additional insight, we reached out to the nonpartisan Pew Hispanic Center, which estimates the size of the illegal immigration population in each state. Here are Pew’s figures on the size of Virginia’s illegal immigrant population by year:

•2005 - 250,000

•2006 - 250,000

•2007 - 250,000

•2008 - 275,000

•2009 - 250,000

•2010 - 275,000

For 2011 and 2012, the latest years for which figures are available, the size of the illegal immigrant population also was 275,000, Pew found.

So when Kaine entered office in 2006, the size of the illegal immigrant population was 250,000, it rose to 275,000 in 2008 and then went back down to its original level during 2009, his last full year in office, according to the Pew figures.

If you go to 2010, during which Kaine served only the first two weeks, the illegal immigrant population was 275,000 - or 25,000 higher than when he entered the governor’s mansion.

While a 10 percent increase in the illegal immigrant population between 2006 and 2010 might seem significant, it’s actually not much of a change at all from a statistical perspective, said Jeffrey Passel, a senior demographer at Pew.

Passel explained that the research group’s illegal immigration figures are not meant to be exact figures on the size of the state’s illegal immigrant population. Rather, they are estimates culled from a sample of data collected by the Census Bureau and are subject to rounding. Just like a public polls drawn from a sample, there’s a margin of error involved in the estimates.

During Kaine’s time in office, the annual size of the illegal immigrant population could be 15,000 to 20,000 higher or lower than the mid-range estimate Pew reported each year, according to its report. So it’s possible that a 25,000 increase from year-to-year might not outpace the Pew study’s margin of error.

The bottom line, during Kaine’s tenure the size of the illegal immigrant population remained flat, Passel said.

Nationally, the illegal immigrant population peaked in 2007 at 12.2 million and fell to 11.3 million in 2013, Pew’s figures show. A major reason for that drop was the impact of the Great Recession, Passel told us.

The Trump campaign didn’t respond to a question we posed about how Kaine’s policies as governor would have led to an increase in illegal immigration.

Analysts told us that beyond state laws, many other factors contribute to where illegal immigrants choose to reside.

Michelle Mittelstadt, a spokeswoman for the Migration Policy Institute, told us illegal immigrants often settle in a state based on how its economy is doing, and whether they already have family living there.

Our ruling

Trump said that while Kaine was governor, he "oversaw a huge increase in illegal immigration, a tremendous increase."

But figures from the Pew Hispanic Center show that the size of the illegal immigrant population essentially was flat during Kaine’s term as governor. It’s certainly not the "huge" and "tremendous" increase that Trump makes it out to be.

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